Wilhelm Conrad Roentgen was a German scientist who discovered x-rays through the use of Crookes tube, a tube he used in studying cathode rays that emitted new kinds of invisible ray that was capable of penetrating through a black paper.
After hearing such discovery, Henri Becquerel, a French scientist had also took interest in the connection between the phosphoresence he had already been investigating and the newly discovered rays. He thought that the phosphoresence uranium salts he had been observing and studying might absorb sunlight and emit it as x-rays.
To test such idea which was disproved later on, Becquerel wrapped photographic plates in black paper so that sunlight could not reach them. He then placed the crystals of uranium on top of the wrapped plates and put the whole set up outside, exposed under the sun.
When he developed the plates, he saw an outline of the uranium crystals. He also placed other objects such as coins or cut out metals between the crystals and the photographic film/plate. It also turned out that he could also produced outlines of those shapes.
The scientific meaning of salt is an ionic compound that is formed when an acid and a base reaction take place and is neutralized.
The common meaning of salt (table salt) is specifically the organic mineral of sodium chloride (NaCl) and is digestible.
Ionic salts are often not digestible (or not commonly digested, anyway)
Answer:
When a candle burns, the hydrogen and carbon from the wax combine with the oxygen in the air to become carbon dioxide and water vapor. Most of the matter in the candle ends up as these two gases.
When products form in an exergonic reaction, the <span>energy required to break bonds is less than the energy released from new bonds. This is usually given off as light. I hope this is the answer you are looking for. Looking forward to help you again. Have a great day ahead!</span>
All of them are technically a public good or a service because for a public goods it would be all and service it would be all so.... yah